SOLUTION: A cell phone Co. offers a contract for which the cost C, in dollars,of t minutes of telephoning is given by C=0.25(t-600)+57.95, it is assumed that t is = to or > 600 minutes. W
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-> SOLUTION: A cell phone Co. offers a contract for which the cost C, in dollars,of t minutes of telephoning is given by C=0.25(t-600)+57.95, it is assumed that t is = to or > 600 minutes. W
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Question 198351: A cell phone Co. offers a contract for which the cost C, in dollars,of t minutes of telephoning is given by C=0.25(t-600)+57.95, it is assumed that t is = to or > 600 minutes. What times will keep cost between $96.70 and $141.20?
My answer:
C=0.25(t-600)+57.95
substitute
96.70=0.25(t-600)+57.95
96.70=0.25t-150+57.95
=188.75=.25t
t=755
C=0.25(t-600)+57.95
141.20=.25t-150+57.95
=233.25=.25t
t=933 Answer by arallie(162) (Show Source):
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